PHILADELPHIA -- Bill Cosby's lawyers on Thursday asked the judge in his upcoming sexual assault retrial to step aside, arguing the judge could be seen as biased because his wife is a social worker who has described herself as an "activist and advocate for assault victims."

Cosby's lawyers contend some of Judge Steven O'Neill's recent pretrial rulings could give the appearance he's being influenced by his wife's work, particularly his decision last week to let prosecutors have up to five additional accusers testify when he allowed just one at the first trial.

O'Neill did not immediately rule on the request. He and his wife, Deborah, did not immediately respond to messages seeking comment.

Deborah O'Neill is a psychotherapist at the University of Pennsylvania and coordinates a team providing care, support and advocacy for student sexual assault victims. In 2012, she wrote her doctoral dissertation on acquaintance rape, the type of assault at issue in Cosby's criminal case.

Last year, Cosby's lawyers said, Deborah O'Neill gave money to a group linked to an organization that's planning a protest outside the retrial.

Cosby has pleaded not guilty to charges he drugged and molested former Temple University athletics administrator Andrea Constand at his suburban Philadelphia home in 2004.

Cosby's first trial ended in a hung jury last year. Jury selection in his retrial is scheduled to start April 2.

Seeking a new judge is the latest attempt the 80-year-old Cosby's retooled defense team has made to push back the start of his retrial.

O'Neill rejected a request last week to delay the retrial at least three months so Cosby's lawyers, led by former Michael Jackson lawyer Tom Mesereau, could have more time to prepare for the five additional accuser witnesses.

Cosby's wife, Camille, blasted O'Neill after the first trial as "overtly arrogant and collaborating with the district attorney," but his lawyers back then never objected to him presiding over the case.

Making the case that Deborah O'Neill's work should disqualify her husband could be tough.

Cosby's new legal team cited just one relevant case. But in that case, a judge's spouse worked as a deputy district attorney. The team also referenced judicial rules that bar judges from letting family interests influence their conduct.

If O'Neill refuses to drop out, Cosby's lawyers said he should let them appeal the decision right away.

The lawyers argued in their filings that O'Neill first gave an appearance of bias at the first trial when he refused to let jurors hear from a woman who claimed Constand told her she wanted to falsely accuse a famous person of sexual misconduct so she could sue and get money.

They also cited O'Neill's insistence that the retrial go on, despite telephone records, travel itineraries and other evidence showing the alleged assault could not have happened in January 2004, when Constand says it did, and thus falls outside the statute of limitations. O'Neill said he would leave that for the jury to decide.